hardhat

This release adds support for verifying contracts in the Avalanche Mainnet and Fuji chains, and in the Moonriver chain.

Thanks to @marcelomorgado and @x0s0l for their contributions!

This release adds support for solidity 0.8.5–0.8.9. It also:

• Adds the personal_sign RPC method. This makes the signMessage method work with Hardhat in the newer versions of ethers.js (closes #1981)
• Adds a new hardhat_getAutomine method that can be used to get the current setting of interval mining (thanks @sisco0!) (closes #2010)
• Enables solc's metadata by default (thanks @chriseth!)
• The node task now shows a warning when the default accounts are used, explaining that those accounts shouldn't be used in live networks with real value.
• Hardhat now throws an error if a version of solc older than 0.4.11 is used. This didn't work anyway, but the error is more clear now.

This release adds support for the Arbitrum Testnet and the FTM Testnet. Thanks to @kr1p70n1c and @polarf0x0 for their contributions!

This release fixes two issues:

• A bug that prevented Hardhat to compile files that concatenated several strings (#1801)
• A bug in our implementation of eth_feeHistory (#1848)

This release adds support for the networkMode specification. Thanks to @FabijanC for the contribution!

This release fixes an issue that broke Hardhat Network when contracts were compiled in the middle of its execution

This release adds a new sample project with a TypeScript setup. It also makes some improvements in the Advanced sample project.

This release fixes a bug (#1885) that prevented the plugin to work with custom Hardhat Network accounts (Thanks @swaylock!)

This release fixes a bug (#1885) that prevented the plugin to work with custom Hardhat Network accounts (Thanks @swaylock!)

This release makes contract.skip and contract.only work in both truffle plugins (Thanks @frangio!)

This release makes contract.skip and contract.only work in both truffle plugins (Thanks @frangio!)

This release fixes a bug in Hardhat Network's solidity source maps processing. Thanks @paulberg!

This release fixes a bug (#1564 ) that prevented Hardhat Network's tracing engine from working if an interface was used as a mapping key. Huge thanks to @k06a for their contribution!

This release fixes an issue (#1828) with networks that support eth_feeHistory but that don't support EIP-1559.

This release adds support for verifying contracts in Arbiscan, the block explorer for Arbitrum.

This PR fixes three issues.

• The Hardhat node had an issue when you connected to it via websocket. Now websocket connections should work fine.
• debug_traceTransaction can be used with transactions sent from impersonated accounts.
• evm_setNextBlockTimestamp, evm_increaseTime and evm_mine now will accept hex strings as arguments.

Additionally, there’s a new advanced sample project that creates a realistic project boilerplate. Try it by running npx hardhat in an empty directory and choosing the “Create an advanced sample project” option.

Thanks to @ngotchac, @shuklaayush and @wolflo for their contributions!

This version fixes a problem with verification in the Optimism networks.

Huge thanks to @mds1 for working on this!

PR: #1775

This release enables the London hardfork by default in the Hardhat Network, changes some other default values in the configuration, and drops support for Node 10.

All of these are technically breaking changes, but most users shouldn't be affected by them. If you want to preserve the previous behavior, use Hardhat v2.5.0, or explicitly set the updated configuration values to their previous defaults.

The default values that have changed are:

• hardfork: the previous default was "berlin", the new default is "london"
• blockGasLimit: the previous default was 12_450_000, the new default is 30_000_000
• gasPrice: the previous default was 8_000_000_000, the new default is "auto".

Read this document to learn more about how we use semver and why and how we introduce breaking changes.

This release adds istanbul and muirGlacier as accepted hardforks in hardhat-ganache.

This release adds support for the upcoming London hardfork to Hardhat.

Enabling the London support

This version of Hardhat doesn't run Hardhat Network using London by default. To use this hardfork, you need to have these config fields:

networks: {
  hardhat: {
    hardfork: "london",
    gasPrice: "auto"
  } 
}

Base fee selection

The London hardfork includes the long-awaited EIP-1559, which changes how transactions pay to be included in the Ethereum blockchain. This includes a new concept called base fee.

To configure the base fee of the first local block, set the initialBaseFeePerGas property in the Hardhat Network configuration:

module.exports = {
  networks: {
    hardhat: {
      initialBaseFeePerGas: 1_000_000_000
    }
  }
}

You can also change this value at runtime using the new hardhat_setNextBlockBaseFeePerGas JSON-RPC method:

await network.provider.send("hardhat_setNextBlockBaseFeePerGas", ["0x77359400"])

Forking London-enabled networks

This release fixes an issue that prevented Hardhat Network from forking Ropsten, Goerli, Rinkeby, and any other network where London has already been activated.

You can now fork them, even if you are not running London locally.

Minimum gas price and the London Hardfork

Hardhat 2.4.0 introduced two ways of controlling the minimum gas price that transactions needed to pay. These are the minGasPrice Hardhat network config field and the hardhat_setMinGasPrice JSON-RPC method.

This functionality is disabled when using the London hardfork. Trying to set the config field or using the JSON-RPC method will result in an error.

Future release and default config values

Hardhat 2.6.0 will be released on August 4, 2021, when London activates on Mainnet. It will update Hardhat Network's default config values to better reflect Mainnet without any modification. This will make London the default hardfork but other default values might also change.